Vertical uprights are known in the art that consist of bent sheet metal slides, drawn aluminum slides or extruded plastic material slides.
By virtue of their structure and their shape these slides can also constitute the vertical uprights of a service door of the flexible curtain type.
These slides are generally produced in one part or at most two parts and have certain drawbacks in that they are exposed to impact with the risk of irreparable damage necessitating complete replacement.
There are also known from the applicant's patent No. EP 0979340 vertical service door uprights including taut flexible slides on a bent sheet metal structural section.